Integrated circuit designs have relied on current references with current mirrors for biasing transistor gain and logic stages. Numerous current references have been devised to improve the performance of integrated circuits. One example of a current reference utilizing current mirrors for biasing is described in U.S. Pat. No. 4,329,639 to Davis entitled "Low Voltage Current Mirror", the basic circuit being shown in FIG. 1, and labelled prior art. While this current reference has been used successfully for many years in conventional bipolar integrated circuit designs, it and other circuit designs have not proven to be optimal when used in integrated circuits utilizing I.sup.2 L devices. This non-optimal operation is largely due to the fact the current delivered by the reference does not track the injector current requirements of I.sup.2 L devices. The lack of tracking is due to processing, operating voltage and temperature variations which is required to maintain constant propagation delays in the circuits being powered. In order to compensate for these variations, prior art current references provided injector currents as much as 2.5 times higher than required to guarantee circuit performance over all processing and operating conditions. This resulted in substantially higher current consumption than actually required when employing I.sup.2 L circuit designs.
There remains a need for a current reference that is capable of compensating for processing and temperature and operating voltage variations for I.sup.2 L devices.